1. Field of the Invention
The present invention relates to an image sensor of a copying apparatus, a facsimile apparatus, a video camera recorder, or the like and to an image sensor for an automatic focusing of a camera. More particularly, the invention relates to an image sensor having an image signal process such as pattern recognition, detection of a moving image, or the like.
2. Related Background Art
As a sensor to recognize an image (video image) as an object, there is a report by Kazuo Kyuma, "Optical neural net and intelligent sensor", the lecture papers of the fourth image input technique symposium, pages 71 to 78, Nov. 10, 1992.
The above conventional technique, however, has the following technical subjects.
(1) Since an optical current is read out, it can be read out in only one direction and a pattern recognizing precision is low. PA1 (2) Even in case of (64.times.64) pixels, it takes a time of 200 .mu.sec for a (outline) process. PA1 (3) Since a Schottky is formed by a comb-shaped Al metal film, a numerical aperture of a photosensitive device is small and a sensitivity is low. PA1 (4) Since a current is read out, a layout pattern of read-out wirings is complicated. PA1 (5) Noises cannot be removed and it is difficult to perform an image process at a high precision.